WO2019019003A1

WO2019019003A1 - Method for manufacturing automobile license plate

Info

Publication number: WO2019019003A1
Application number: PCT/CN2017/094256
Authority: WO
Inventors: 钱庙根; 李逢春; 季明明
Original assignee: 湖州泰和汽车零部件有限公司
Priority date: 2017-07-25
Filing date: 2017-07-25
Publication date: 2019-01-31

Abstract

Disclosed is a method for manufacturing an automobile license plate, which method is applied in a driving-assistance system. The method comprises the following steps: injection molding, wherein license plate base materials of various shapes are formed by injection molding; pretreatment of the base materials, wherein the obtained base materials are subjected to dust removal and electrostatic elimination treatments; vacuum plating, wherein two vacuum plating layers, i.e. an indium alloy plating layer and an oxide protection plating layer, are formed on the surfaces of the base materials by means of a vacuum plating method, the total thickness being less than 1 μm, and the thickness of the indium alloy plating layer being controlled such that same is within 10-60 nm; deplating, wherein according to requirements for different automobile license plates, a plating-resistant paint is applied on the vacuum plating layers and then, a deplating treatment is performed; applying a colored paint layer; applying a protective paint layer; bonding to a base; and inspecting and packaging. The method for manufacturing an automobile license plate can ensure that a license plate has a good metal feeling, sufficient strength, high stability, a long service life and a good production qualification rate, and in addition, the performance of a radar is not affected.

Description

Method for manufacturing automobile signage

Technical field

[0001] This project relates to the technical fields related to advanced manufacturing and automation of automobiles and rail vehicles, and in particular to an advanced manufacturing method for an automobile signage used in advanced driver assistance systems.

Background technique

[0002] As the name suggests, automobile signs are a symbol of automobile brands. They are often attached to the front and rear of the car, and the position is centered for marking and easy identification. Automobile signs generally have silver-colored areas and color areas. For example, the public signage only has the "v" "w" pattern and the circle outside the pattern is silver and bright, and the rest is the color area. The silver and bright areas of various signs are different. Since existing vehicles are equipped with radar, it is necessary for the vehicle signs to ensure that the radar waves pass through without affecting the radar work, especially for vehicles with adaptive cruise systems, the front radar is used to judge and the preceding vehicles. Distance, in response to such distance and other parameters to adjust the speed of the vehicle, etc. For such applications, automotive signs can be very important to penetrate radar waves.

[0003] Traffic safety has always been the focus of the general public. To ensure the safety of driving vehicles, countries around the world have invested a lot of manpower, material resources and financial resources in the research and development of automobile collision avoidance technology. The Adaptive Cruise Control (ACC) application allows the driver to maintain proper speed and control the distance to the vehicle in front. Scanning the road ahead with the on-board radar, and with the wheel speed sensor to keep the set distance between the vehicle and the front vehicle, the speed of the front vehicle is reduced, the vehicle automatically brakes and maintains the safe distance, the speed of the front vehicle increases, and the vehicle will automatically speed up to Set the speed. This reduces manual operation and greatly improves driving comfort and safety.

[0004] The prior art, such as the patent CN183842B, provides a metallic lustrous decorative article for use in a beam path of a radar device, comprising a substrate composed of a transparent resin layer, tin and/or tin disposed on the back surface of the substrate. An alloy layer, and a decorative lacquer layer disposed on the back side of the tin and/or tin alloy layer. The molded article described in this patent has a delicate metal design similar to that of chrome plating, and ensures that the transmission loss of the radar millimeter wave is 1. 6 to 1.8 db.

[0005] Patent CN103956573A provides a method for preparing a radar protective cover, and the hot stamping step in the preparation process can not effectively avoid the influence of dust, stains, water vapor and the like in the air, thereby reducing the production. The appearance compliance rate and product qualification rate of the product, the thickness of the indium-plated alloy nano metal layer in the step described in the patent is 5-50 nm, although the transmission loss of the radar millimeter wave is ensured to be less than 2 db, but in the actual production process The pass rate of the product is only 60<3⁄4~68<3⁄4.

technical problem

[0006] The current development of the automotive industry puts higher demands on the manufacturing technology of automobile signs, which has good metal texture, sufficient strength, high stability, long service life and good production yield. At the same time, the influence of radar electromagnetic wave transmission is minimal and does not affect the performance of radar. However, the prior art is difficult to meet the above requirements.

Problem solution

Technical solution

The present invention provides a method of manufacturing an automobile sign. It not only retains the silvery, hard and unique appearance inherent in most automobile signs, but also meets the requirements of radar wave round-trip transmission loss below 1.4db.

[0008] In order to achieve the object, the present invention adopts the following technical solutions:

[0009] A vehicle sign manufacturing method, characterized in that, in order comprises the following steps:

[0010] (1), injection molding: transparent substrate by injection molding to form a variety of shaped signage substrate;

[0011] (2), substrate pretreatment: pre-treatment of the (1) formed label substrate;

[0012] (3), vacuum plating: through the (2) treated label substrate by magnetron sputtering or vacuum evaporation method in the entire area of the back of the formation of indium alloy layer and protective coating;

[0013] (4), deplating: the protective coating and indium alloy layer formed by (3) according to the requirements of different automobile signs, the areas requiring silver bright color are coated with the anti-corrosive paint, the physical area of the uncoated anti-painting area is used. Or chemically removed;

[0014] (5), paint layer: painted on the surface formed by (4), to meet the color requirements of the area outside the silver bright color coating, the same can also play the role of protecting the vacuum coating;

[0015] (6), protective lacquer layer: spraying a protective lacquer layer on the other surface of the label substrate obtained by (5); [0016] (7), bonding with the pedestal: will be treated by (6) The label substrate is bonded to the base;

[0017] (8) Inspection packaging: The product is inspected after the (7) processed label, and the label is attached and stored in the warehouse.

[0018] The advantages of the preparation method of the invention are: [0019] (1) Vacuum plating is directly performed after the pretreatment of the substrate is completed, which reduces the processes of spraying primer or hot stamping or printing in other schemes, thereby avoiding the risk of dust, stains, moisture and the like in the production process. This scheme has the greatest impact on the pass rate of finished products, and the pass rate is significantly higher, increasing from 60%~68<3⁄4 to over 85%, resulting in increased production capacity and significantly reduced production costs.

[0020] (2) Vacuum coating is a key technology of the present invention, especially an indium-plated alloy, and the film thickness is controlled at 10 to 60 nm, which enhances the stability of the film layer, thereby improving the yield of the film, requiring a film. The thickness is much smaller than the electron mean free path, and the metal film structure does not reach complete continuity, so that the surface resistance of the metal film is large, that is, the sheet resistance is 20 kΩ or more. Using a simple instrument in production, through the surface resistance test, it can be basically judged whether the attenuation rate of the product radar wave crossing the sign is up to standard, and the attenuation rate can be controlled below 1.4db.

[0021] (3) The deplating process is applied to the automobile signage, has strong adaptability, and can satisfy a variety of different structures and shapes.

, remove the unnecessary vacuum coating outside the silver bright area by physical or chemical means to meet the requirements of different types of automobile signs.

[0022] (4) Spraying the protective lacquer layer after deplating, can avoid defects such as cracking of the sign substrate due to external air or sunlight, yellowing after aging, and the same can make the sign more resistant to gravel. When the physical impact, and the water absorption of the sign is less than 0.1%, it can ensure that the radar wave can be transmitted normally under normal rainy weather, wherein the UV is cured by ultraviolet radiation and is more environmentally friendly.

[0023] (5) According to the penetration characteristics of the millimeter wave, the overall thickness and material of the substrate have a great influence on the penetration of the millimeter wave, and therefore the thickness needs to be uniform in the range of the cone of the radar. The transparent substrate is used to satisfy the shape of the automobile sign, and the base is bonded together to meet the overall thickness requirement of the sign, and the thickness requirements of the sign are determined according to the different emission wavelengths of the radar. The dielectric constant of the transparent substrate and the pedestal should be as close as possible or close to each other. The gap between the transparent substrate and the pedestal should be < 0.21^^ otherwise the air between the two will affect the radar wave function or increase the attenuation. .

[0024] Preferably, the transparent substrate in the step (1) is made of polycarbonate, which is heat-resistant, impact-resistant, creep-resistant and dimensionally stable.

[0025] Preferably, the pre-treatment in the step (2) is specifically performing electrostatic dust removal on the substrate, warming and de-stressing, then dusting with a brush, and finally cleaning with dry ice. Remove the stress of the substrate by baking to a certain temperature, and then neutralize the surface of the substrate by neutralizing the surface of the substrate with high-speed airflow, and then use the brush The ostrich hair brush machine acts on the surface of the substrate, disturbs the scouring action, removes the dust on the surface of the substrate, and is carried away by the airflow. Finally, the substrate is cleaned with dry ice, so that the pretreatment is thoroughly performed to ensure the coating. the quality of.

Preferably, in the step (3), the indium alloy layer and the protective layer are plated by vacuum evaporation, and the evaporation source for plating the protective layer is an e-type electron gun.

[0027] Preferably, the total thickness of the indium alloy layer and the protective plating layer in the step (3) is less than 1 μm.

[0028] Preferably, the thickness of the indium alloy layer in the step (3) is controlled to be 10 to 60 nm, the film thickness is much smaller than the electron mean free path, and the metal thin film structure is not completely continuous.

[0029] Preferably, the surface sheet resistance of the indium alloy layer in the step (3) is 20 kΩ or more.

[0030] Preferably, the metal component of the indium alloy layer in the step (3) is indium and one or more of tin, gallium, silver, and antimony having a mass percentage of 0 to 10 <3⁄4. The metal composition of the nano-metal layer is matched with each plating layer. Even if the sign has a good metallic luster, the millimeter wave emitted by the radar can travel back and forth across the sign, and there is almost no attenuation, which ensures the effectiveness of the radar.

More preferably, the indium alloy is an indium alloy containing 5 wt% of silver. This component enables the sign to have good metallic luster, sufficient strength and low radar millimeter wave attenuation.

Preferably, the protective film layer in the step (3) is an oxide film layer whose composition is silica. The silica composition and thickness of the oxide protective layer help to protect the nano metal layer, so that the millimeter wave emitted by the radar can pass through the protective cover, and there is almost no attenuation, and the sign has a better metallic luster. The obvious signage of the sign and the effectiveness of the radar are guaranteed to ensure the safety of the driving.

[0033] Preferably, the resist paint in the step (4) is a resin varnish, and the resin used in the selected resin varnish should be a strong alkali resistant resin, preferably a bisphenol A epoxy vinyl ester resin, The resin varnish is a clear lacquer and is resistant to strong alkali. It can protect the sign and the silver bright effect of the silver bright area. The coating covered by the 吋 protection is not corroded by the sodium hydroxide solution.

[0034] Preferably, the solution used in the chemical mode in the step (4) is a NaOH solution. The coating which is not protected by the enamel coating is dissolved by the NaOH solution, and the temperature of the solution is controlled at 60 ° C to 80 ° C. The deplating effect is best in this temperature range. After the deplating is completed, the surface of the label is cleaned with pure water to ensure There are no residual reagents. The solvent of the NaOH solution is deionized water or distilled water, and the solute includes NaOH, NaSi03, sodium hydroxyethylidene diphosphonate, a corrosion inhibitor and a surfactant, wherein the solution is strongly alkaline after the NaOH and NaS are dissolved in water. Chemically reacts with unwanted coatings on the surface of the substrate to remove unwanted coatings on the surface. Sodium hydroxyethylidene diphosphinate acts as a chelating agent and forms compounds with both coordinating bonds and covalent bonds with metal indium ions. The etchant protection label substrate is not corroded by the NaOH solution. One or more of sodium aluminate, sodium nitrite and sodium nitrate may be selected, preferably sodium aluminate. The surfactant reduces the surface tension of water and helps the dioxide. The silicon is uniformly dissolved in the NaOH solution, and the sodium butyl naphthalene sulfonate is selected. The content of each component of the solute is: NaOH (25~5 Og/L), sodium silicate (150~185)

g/L), sodium hydroxyethylidene diphosphonate (10~50g/L), corrosion inhibitor (2~5g/L), sodium butylnaphthalene sulfonate

(l~5 g/L). Due to the reasonable composition and content design, it can quickly and evenly remove the coating which is not needed on the surface of the label, and reduce the damage to the label substrate. The deplating solution has low production cost, high stability and long service life. Features.

[0035] The preparation method of the preferred NaOH solution comprises the following steps:

[0036] (1), adding 1 L of deionized water to the container;

[0037] (2), adding corrosion inhibitor 2~5g, heated to 60 ° C, constant temperature stirring for 60min;

[0038] (3), adding sodium butyl naphthalene sulfonate l~5 g, stirring for 30 min;

[0039] (4), after the temperature is lowered to room temperature, add sodium hydroxide 25~50g, sodium silicate 150~185g and hydroxyethylidene: sodium phosphonate 10~50g, continue to stir until it returns to room temperature .

Preferably, the protective paint sprayed in the step (6) is UV or PU. By spraying UV or PU on the surface of the sign, it can solve the defects that the substrate is not resistant to light, yellowing after aging, and the same can make the sign more resistant to physical impact such as crushed stone, and the water absorption of the sign is less than 0.1%, which can ensure the radar wave can It can also be transported normally in normal rainy weather, where UV is cured by UV radiation and is more environmentally friendly.

[0041] Preferably, the step (7) bonds the treated label substrate and the base with glue or other means, and the gap between the label substrate and the base should be < 0.2 mm, and a layer is formed. An automobile sign with a uniform wall thickness. After the transparent sign is completed, the base is glued with the glue, and the thickness of the sign is controlled according to the radar frequency. The back side of the base is affixed with a one-way gas permeable film to discharge the water vapor between the transparent sign and the pedestal. Will enter, so that it will not interfere with the penetration of radar waves by water vapor.

Advantageous effects of the invention

Beneficial effect

[0042] The advantages of the preparation method of the invention are: [0043] (1) Vacuum plating is directly performed after the pretreatment of the substrate is completed, which reduces the processes of spraying primer or hot stamping or printing in other schemes, thereby avoiding the risk of dust, stains, moisture, and the like in the production process. This scheme has the greatest impact on the pass rate of finished products, and the pass rate is significantly higher, increasing from 60%~68<3⁄4 to over 85%, resulting in increased production capacity and significantly reduced production costs.

[0044] (2) Vacuum coating is a key technology of the present invention, especially an indium-plated alloy, and the film thickness is controlled at 10 to 60 nm, which enhances the stability of the film layer, thereby improving the yield of the film, requiring a film. The thickness is much smaller than the electron mean free path, and the metal film structure does not reach complete continuity, so that the surface resistance of the metal film is large, that is, the sheet resistance is 20 kΩ or more. Using a simple instrument in production, through the surface resistance test, it can be basically judged whether the attenuation rate of the product radar wave crossing the sign is up to standard, and the attenuation rate can be controlled below 1.4db.

[0045] (3) The deplating process is applied to the automobile signage, has strong adaptability, and can satisfy a variety of different structures and shapes.

[0046] (4) Spraying the protective lacquer layer after deplating, can avoid defects such as cracking of the sign substrate due to external air or sunlight, yellowing after aging, and the same can make the sign more resistant to crushed stone. When the physical impact, and the water absorption of the sign is less than 0.1%, it can ensure that the radar wave can be transmitted normally under normal rainy weather, wherein the UV is cured by ultraviolet radiation and is more environmentally friendly.

[0047] (5) According to the penetration characteristics of the millimeter wave, the overall thickness and material of the substrate have a great influence on the penetration of the millimeter wave, and therefore the thickness needs to be uniform in the range of the cone of the radar. The transparent substrate is used to satisfy the shape of the automobile sign, and the base is bonded together to meet the overall thickness requirement of the sign, and the thickness requirements of the sign are determined according to the different emission wavelengths of the radar. The dielectric constant of the transparent substrate and the pedestal should be as close as possible or close to each other. The gap between the transparent substrate and the pedestal should be < 0.21^^ otherwise the air between the two will affect the radar wave function or increase the attenuation. .

Brief description of the drawing

DRAWINGS

1 is a schematic view showing the relationship between the various levels of the automobile sign and the orientation of the automobile sign and the radar;

2 is a process road diagram of a method for preparing an automobile sign according to an embodiment of the present invention;

[0050] wherein, 1-label substrate, 2-vacuum coating, 3-color lacquer layer, 4-coat layer, 5-base. Embodiments of the invention

Embodiment 1

[0052] The car signage of a certain type of car, the product structure sectional view is shown in Figure 1. The process route is shown in Figure 2.

[0053] The placard corresponds to a radar frequency of 24.1 GHz, and the total thickness of the parts (section 1-5) is 7.65 ± 0.15 mm. The transparent substrate and the pedestal are made of thermoplastic engineering plastic polycarbonate, which is heat and shock resistant. Resistance to creep and dimensional stability.

[0054] The transparent substrate is formed into a desired shape of the label substrate 1 by injection molding.

[0055] After the injection molding of the label substrate, the stress relief baking is performed at 110 ° C for 2 hours. After the baking is completed, the label substrate is loaded into the vacuum plating tool to remove dust and static electricity.

[0056] The vacuum plating layer is divided into two layers, the total thickness is less than 1μηι, the first indium alloy layer is plated, and the thickness is controlled at 10 nm~2

5nm, the film thickness is required to be much smaller than the electron mean free path, and the metal film structure does not reach complete continuity.

Therefore, the surface resistance of the metal film is large, that is, the sheet resistance is 20 kΩ or more. A second layer of a silicon oxide oxide is applied to protect the indium alloy layer.

[0057] The vacuum-plated finished label is coated with a resist paint at a position where the plating layer needs to be retained to protect the desired plating layer, and then placed in a prepared NaOH solution for deplating treatment, and the solution temperature is required to be 70 ° C. After the deplating is completed, the surface of the sign should be cleaned with pure water. There must be no residual reagents. The deplating area is shown by a dotted line in Figure 1.

[0058] Spray paint layer 3, the other parts of the vacuum coating are required to be black, so the black paint is sprayed, and the paint can also protect the vacuum coating without affecting the appearance and performance of the label substrate.

[0059] In order to solve the defect that the selected label substrate is not resistant to light, the surface of the transparent substrate is sprayed with UV to form the coating layer 4, so as to ensure that the sign does not have defects such as yellowing after aging, and the same can make the sign resistant to the impact of the stone. , and the water absorption of the sign is less than 0.1%, thus ensuring that the signage radar wave can be transmitted normally in normal rainy weather.

[0060] After the transparent sign is completed, the base 5 is glued with the glue, and the thickness of the radar wave penetration receiving area of the control product is controlled within the range of 7.65±0.15 mm, and the gap between the label substrate and the base is less than 0.2. Mm, a unidirectional gas permeable membrane is attached to the back of the base to allow the water vapor between the transparent sign and the pedestal to be discharged, and the water vapor will not enter. , will not interfere with the penetration of radar waves by water vapor.

[0061] After the product has passed the inspection, it is labeled and stored in the warehouse.

Embodiment 2

[0063] The car signage of a certain type of car, the product structure sectional view is shown in Figure 1. The process route is shown in Figure 2.

[0064] The sign corresponds to a radar frequency of 24.1 GHz, and the total thickness of the parts (section 1-5) is 7.65 ± 0.15 mm. The transparent substrate and the base are made of thermoplastic engineering plastic polycarbonate, which is heat and shock resistant. Resistance to creep and dimensional stability.

[0065] The transparent substrate is formed into a desired shape of the label substrate 1 by injection molding. After the injection molding of the sign substrate, it needs to be destressed and baked at 110 ° C for 2 h. After the baking is completed, the label substrate is placed in a vacuum plating tool to remove dust and static electricity.

[0066] The vacuum plating layer is divided into two layers, the total thickness is less than 1 μm, the first indium alloy layer is plated, the thickness is controlled at 25 nm to 45 nm, the film thickness is required to be much smaller than the electron mean free path, and the metal film structure is not completely continuous. Therefore, the surface resistance of the metal film is large, that is, the sheet resistance is 20 kΩ or more. A second layer of a silicon oxide oxide is applied to protect the indium alloy layer.

[0067] The vacuum-plated label is coated with a resist paint at a position where the plating layer needs to be retained to protect the plating layer, and then placed in a prepared NaOH solution for deplating, requiring the solution temperature to be 70 ° C, deplating After completion, the surface of the sign must be cleaned with pure water. There must be no residual reagents. The deplating area is shown by a dotted line in Figure 1.

[0068] Spray paint layer 3, the other parts of the vacuum coating are required to have a black color, so the black paint is sprayed, and the paint can also protect the vacuum coating without affecting the appearance and performance of the label substrate.

[0069] In order to solve the defect that the selected label substrate is not resistant to light, the surface of the transparent substrate is sprayed with UV to form the coating layer 4, so as to ensure that the sign does not have defects such as yellowing after aging, and the same can make the sign resistant to the impact of the stone. , and the water absorption of the sign is less than 0.1%, thus ensuring that the signage radar wave can be transmitted normally in normal rainy weather.

[0070] After the transparent sign is completed, the base 5 is glued with the glue, and the thickness of the radar wave penetration receiving area of the control product is controlled within the range of 7.65±0.15 mm, and the gap between the label substrate and the base is less than 0.2. Mm, a unidirectional gas permeable membrane is attached to the back of the base to allow the water vapor between the transparent sign and the pedestal to be discharged, and the water vapor will not enter, and the water vapor will not interfere with the penetration of the radar wave. [0071] After the product has passed the inspection, it is labeled and stored in the warehouse.

Embodiment 3

[0073] The car signage of a certain type of car, the product structure sectional view is shown in Figure 1. The process route is shown in Figure 2.

[0074] The placard corresponds to a radar frequency of 24.1 GHz, and the total thickness of the parts (section 1-5) is 7.65 ± 0.15 mm. The transparent substrate and the pedestal are made of thermoplastic engineering plastic polycarbonate, which is heat and shock resistant. Resistance to creep and dimensional stability.

[0075] The transparent substrate is formed into a desired shape of the label substrate 1 by injection molding. After the injection molding of the sign substrate, it needs to be destressed and baked at 110 ° C for 2 h. After the baking is completed, the label substrate is placed in a vacuum plating tool to remove dust and static electricity.

[0076] The vacuum coating layer 2 is divided into two layers, the total thickness is less than 1 μm, the first indium alloy layer is plated, the thickness is controlled at 45 nm~6 Onm, the film thickness is required to be much smaller than the electron mean free path, and the metal film structure is not completely continuous. Therefore, the surface resistance of the metal film is large, that is, the sheet resistance is 20 kΩ or more. A second layer of a silicon oxide oxide is applied to protect the indium alloy layer.

[0077] The vacuum-plated label is coated with a resist paint at a position where the plating layer needs to be retained to protect the plating layer, and then placed in a prepared NaOH solution for deplating, requiring the solution temperature to be 70 ° C, deplating After completion, the surface of the sign must be cleaned with pure water. There must be no residual reagents. The deplating area is shown by a dotted line in Figure 1.

[0078] Spray paint layer 3, the other parts of the vacuum coating are required to have a black color, so the black paint is sprayed, and the paint can also protect the vacuum coating without affecting the appearance and performance of the label substrate.

[0079] In order to solve the defect that the selected label substrate is not resistant to light, the surface of the transparent substrate is sprayed with UV to form the coating layer 4, so as to ensure that the sign does not have defects such as yellowing after aging, and the same can make the sign resistant to the impact of the stone. , and the water absorption of the sign is less than 0.1%, thus ensuring that the signage radar wave can be transmitted normally in normal rainy weather.

[0080] After the transparent sign is completed, the base 5 is glued with the glue, and the thickness of the radar wave penetration receiving area of the control product is controlled within the range of 7.65±0.15 mm, and the gap between the label substrate and the base is less than 0.2. Mm, a unidirectional gas permeable membrane is attached to the back of the base to allow the water vapor between the transparent sign and the pedestal to be discharged, and the water vapor will not enter, and the water vapor will not interfere with the penetration of the radar wave.

[0081] After the product has passed the inspection, it is labeled and stored in the warehouse. Embodiment 4

[0083] The same as the first embodiment, the difference is in the NaOH solution required for the deplating process, the solvent is 1L deionized water, the solute is NaOH 25g, sodium silicate 150g, sodium hydroxyethylidene diphosphonate 10g, sodium aluminate 2g , sodium butyl naphthalene sulfonate l _g , the preparation method thereof comprises the following:

[0084] (1), adding 1 L of deionized water to the container;

[0085] (2), adding 2 g of sodium aluminate, heated to 60 ° C, stirring at constant temperature for 60 min;

[0086] (3), adding sodium butyl naphthalene sulfonate l g, stirred for 30 min;

[0087] (4) After the temperature was lowered to room temperature, 25 g of sodium hydroxide, 150 g of sodium silicate and 10 g of sodium hydroxyethylidene diphosphonate were added, and stirring was continued until it returned to room temperature.

[0088] Embodiment 5

[0089] The same as the first embodiment, the difference is in the NaOH solution required for the deplating process, the solvent is 1L deionized water, the solute is NaOH 50g, sodium silicate 185g, sodium hydroxyethylidene diphosphonate 50g, sodium aluminate 5g , sodium butyl naphthalene sulfonate 5g, the preparation method thereof comprises the following:

[0090] (1), adding 1 L of deionized water to the container;

[0091] (2), adding sodium aluminate 5g, heated to 60 ° C, stirring at constant temperature for 60 min;

[0092] (3), adding 5 g of sodium butyl naphthalenesulfonate, stirring for 30 min;

[0093] (4) After the temperature was lowered to room temperature, 50 g of sodium hydroxide, 185 g of sodium silicate and 50 g of sodium hydroxyethylidene diphosphonate were added, and stirring was continued until returning to room temperature.

Embodiment 6

[0095] The same as the first embodiment, the difference is in the NaOH solution required for the deplating process, the solvent is 1L deionized water, the solute is NaOH 38g, sodium silicate 168g, sodium hydroxyethylidene diphosphonate 30g, sodium aluminate 3g , sodium butyl naphthalene sulfonate _3g , the preparation method thereof comprises the following:

[0096] (1), adding 1 L of deionized water to the container;

[0097] (2), adding sodium aluminate 3g, heated to 60 ° C, stirring at constant temperature for 60 min _;

[0098] (3), adding 3 g of sodium butyl naphthalene sulfonate, stirred for 30 min;

[0099] (4) After the temperature was lowered to room temperature, 38 g of sodium hydroxide, 168 g of sodium silicate and 30 g of sodium hydroxyethylidene were added, and stirring was continued until returning to room temperature.

[0100] The inventors prepared 1L samples according to the NaOH solution configuration methods in Examples 4, 5, and 6 respectively. The amount of substrate corrosion, the amount of dissolved indium and the stability of each sample were measured. The detection method is:

[0101] (1) The amount of corrosion of the substrate: the unplated substrate is immersed in the sample of the deplating solution for 60 minutes, and the mass loss of the substrate before and after weighing;

[0102] (2), the amount of dissolved indium: pure indium is completely immersed in the deplating solution sample until the reaction is complete, the purity of pure indium before and after weighing;

[0103] (3) Stability: The sample of the deplating solution is statically placed at 40 ° C, and the effective concentration of NaOH is measured to be reduced to

The number of days required for 1%.

[0104] The test results are as follows: In the fourth embodiment, the NaOH solution substrate corrosion rate is 0.05g, the dissolved indium amount is 140g, and the stability is 188 days; in the fifth embodiment, the NaOH solution substrate corrosion amount is 0.06g, the dissolved indium amount is 156g, and the stability is stable. In the sixth embodiment, the NaOH solution substrate has a corrosion amount of 0.04 g, an indium content of 168 g, and a stability of 210 days. It can be clearly seen from the above test results that the configuration method of the NaOH solution is the best in the sixth embodiment, the deplating solution is stable, the deplating effect is good, the deplating speed is fast, and the process is simple.

Comparative Example

[0106] Compared with the embodiment in the prior patent CN103956573A, the automobile sign of a certain type of automobile has a radar frequency of 24.1 GHz, and the total thickness of the parts is 7.65±0.15 mm, and the transparent substrate and the base are thermoplastic engineering plastics. Polycarbonate, heat and impact resistant, creep resistant and dimensionally stable. The manufacturing process of this product mainly includes injection molding, pre-treatment, hot stamping, first plating, second plating, and spray coating.

, dispensing, milling gates, inspection packaging.

[0107] Injection molding: The transparent substrate is formed into a desired label substrate by injection molding.

[0108] Pre-treatment: After injection molding of the sign substrate, it is necessary to perform stress-free baking at 110 ° C for 2 h, and perform electrostatic dust removal after baking.

[0109] Hot Stamping: Cover the area where the sign is not required to be bright, and then cover the surface of the label substrate with a black film or a color film according to the label.

[0110] First plating: A nano-indium alloy layer is plated by magnetron sputtering or vacuum evaporation, and the thickness thereof is controlled to be 10 nm to 60 nm, and the surface resistance is 20 kΩ or more.

[0111] Second plating: The silicon dioxide protective layer is plated by magnetron sputtering or electron beam vacuum plating.

[0112] Spraying protective lacquer layer: UV lacquer is sprayed on the surface of the silica protective layer, and UV lacquer is also sprayed on the other surface of the label substrate, and cured by ultraviolet irradiation. [0113] Dispensing: The dispensing substrate is tightly bonded to the base by dispensing.

[0114] Milling gate: Milling the excess handle on the injection molded body.

[0115] Inspection packaging: After the product is inspected, the label is attached and sent to the warehouse for storage.

[0116] The inventors have repeatedly tested the first, second, third and comparative examples, and tested the appearance and decay rate of the produced products and counted the yield and decay rate of the product. The pass rate calculated in the first embodiment is 86%, and the attenuation rate is less than 1.4 db; the pass rate calculated in the second embodiment is 87%, and the decay rate is less than 1.3 db; the pass rate calculated in the third embodiment is 86%. The attenuation rate is less than 1.4 db; the pass rate calculated by the comparative example is 65%, and the decay rate is about 1.8-2.0 db. Therefore, it can be clearly seen that the optimization of the process significantly improves the yield of the product, greatly improves the production efficiency, and improves the attenuation rate of the product.

[0117] The inventors conducted several experiments to improve the pass rate of the sign to improve the pass rate of the sign, and found that the total thickness of the two-layer film plated by vacuum plating is less than lum, and the thickness of the indium alloy layer is 25 nm to 45 nm. The surface resistance of the indium alloy layer is more than 20 kohms and does not reach a continuous structure. After the bonding between the sign and the pedestal is less than 0.2 mm, the resulting sign has the lowest attenuation rate of 1.3 db or less, and the pass rate of the same sign is achieved. More than 85%. However, in actual production, it is also necessary to consider the cost of the material itself, and the cost required for the control of the thickness of the nanofilm, so that these optimal conditions are not all selected.

[0118] The present invention relates to a method for manufacturing an automobile signage, which can provide a good metal texture, sufficient strength, high reliability, and long service life, and affect the transmission of radar electromagnetic waves. A sign that is minimal and does not affect the performance of the radar. This sign is suitable for various radar systems installed in modern cars. It can effectively ensure driving safety and avoid some traffic accidents caused by radar blind spots or radar wave transmission attenuation. According to the automobile sign making method of the invention, it is possible to ensure that the signboard has a decay rate of less than 1.4 db, and the pass rate of the sign is more than 85%. It should be noted that the specific embodiments are merely illustrative of the present invention and are not to be construed as limiting the scope of the invention, and that various modifications and improvements can be made without departing from the structure of the invention. It should also be considered as the scope of protection of the present invention, which does not affect the effects of the practice of the present invention and the utility of the patent. The scope of the claims should be determined by the content of the claims, and the specific embodiments and the like in the specification may be used to explain the claims.

Claims

Claim

[Claim 1] A method for manufacturing an automobile sign, characterized in that: the method comprises the following steps: Injection molding: a transparent substrate is formed into a molding substrate of various shapes by injection molding; substrate pretreatment: 1) forming the label substrate for pretreatment; vacuum plating: forming the indium alloy layer and the protective plating layer on all the back surfaces of the label substrate after the (2) treatment by magnetron sputtering or vacuum evaporation; Plating: The protective coating and indium alloy layer formed by (3) are coated with a resistive paint in the area of silver bright color according to the requirements of different automobile signs, and the uncoated resist paint area is physically or chemically removed;

Paint layer: Paint the painted layer on the surface formed by (4);

Protective lacquer: Apply a protective lacquer layer to the pedestal on the other surface of the resulting label substrate (5): Bond the (6) treated label substrate to the pedestal; inspect the package.

[Claim 2] The method for manufacturing an automobile sign according to claim 1, wherein the pretreatment of the label substrate in the step (2) comprises stress relief baking, dust removal, and static elimination.

[Claim 3] The method for manufacturing an automobile sign according to claim 1, wherein the total thickness of the indium alloy layer and the protective plating layer in the step (3) is less than 1 μm.

[Claim 4] A method of manufacturing an automobile sign according to claim 3, wherein the thickness of the indium alloy layer is controlled to be 10 to 60 nm.

[Claim 5] A method of manufacturing an automobile sign according to claim 3, wherein the indium alloy layer has a surface sheet resistance of 20 kΩ or more.

[Claim 6] The method for manufacturing an automobile sign according to claim 3, wherein the indium alloy layer has a metal component of indium and tin, gallium, silver, and a mass percentage of 0 to 10%. One or more of cockroaches.

[Claim 7] A method of manufacturing an automobile sign according to claim 3, wherein the protective plating layer is an oxide protective layer, and the composition thereof is silica.

[Claim 8] A method of manufacturing an automobile sign according to claim 1, wherein: The solution used in the chemical mode in the step (4) is a NaOH solution.

[Claim 9] The method for manufacturing an automobile sign according to claim 1, wherein the step (6) is sprayed with a protective lacquer of UV or PU.

[Claim 10] The method for manufacturing an automobile sign according to claim 1, wherein the label substrate after the step (7) is adhered to the base by glue or the like. And the clearance between the sign and the base should be < 0.2! ! ^, and ensure that a car logo with a uniform wall thickness is formed.